Pant-like disposable garments are in common use in today's society. For example, disposable absorbent underwear for incontinence and enuresis conditions, disposable training pants, and disposable menstrual panties are common in the marketplace. It is desirable to make such products as much like normal cloth underwear as possible. For example, wearers of incontinence and enuresis garments generally wish to conceal the fact that they are wearing such products, and therefore desire the garments to resemble normal cloth underwear as closely as possible. In another example, children wearing toilet training pants take pride in the fact that they are no longer wearing diapers, and providing them with a disposable training pant product that closely resembles real underwear supports this process. It is also important that such garments provide a snug and secure fit, both to provide comfort to the wearer and to minimize leakage of bodily waste out of the absorbent garment. For example, it is common for many products to include waistbands or leg bands, often elasticized, to provide improved fit, leakage management, and underwear-like aesthetics.
However, creating underwear-like waistbands on disposable garments can be problematic at commercial manufacturing speeds. For example, one conventional disposable pant design employs front and back elastomeric body panels, with a separate elastic waistband attached thereto. Another design employs an integral waistband in which portions of the front and back body panels are folded over and sandwich elastic elements to create the waistband. In both cases, the front panel and back panels are joined together along bonded side seams, commonly via the use of ultrasonic, heat, and/or pressure bonding. In certain regions of the front and back body panels where the waistband resides, the seaming mechanism (e.g., an ultrasonic, heat, and/or pressure bonder) must penetrate not only the waistband materials but the front and back body panel materials as well. In contrast, in the regions of the front and back body panels where the waistband is not present, the seaming mechanism usually must only penetrate the front and back body panel materials to complete the seam. To reduce manufacturing equipment complexity and cost, it is common to use a single seaming mechanism to create an entire side seam, even though such entire side seam extends both through regions where a waistband is present, and regions where no waistband is present. As a result, the single seaming mechanism must be engineered to penetrate both regions adequately, but not in a way that damages either portion.
For example, in a garment in which the front and back body panels are each constructed of an elastomeric film laminate, in which an elastomeric film layer is sandwiched between two nonwoven layers, joining the front panel to the back panel via a pair of side seams requires that the seaming mechanism (e.g., an ultrasonic, heat, and/or pressure bonder) penetrate six layers of material (three layers of the front panel laminate, and three layers of the back panel laminate). If this garment also employs an additional waistband layer constructed of a similar laminate material (whether separately attached or integrally folded), joining the front panel to the back panel in those regions where the waistband is present requires that the seaming mechanism penetrate twelve layers of material (three layers of the front panel laminate, three layers of the back panel laminate, three layers of the front waistband, and three layers of the back waistband). As noted above, as it is common to employ a single seaming operation to create each seam in its entirety, the seaming mechanism in such conventional designs must be aggressive enough to seam the relatively high number of layers in the waistband region, but not so aggressive that the material in the non-waistband regions of the seam becomes damaged, perforated, or burned.
At modest manufacturing speeds, this dilemma can be adequately managed. However, at higher speeds of manufacture, it becomes increasingly difficult to engineer a seaming mechanism to bond both the waistband region and the non-waistband region without encountering the problems mentioned above. Therefore, what is needed is a method of making disposable pant-like garments having waistbands that can help avoid this circumstance.